I'm not a Linux fanboy. In fact, I'm pretty much OS indifferent - so long as the operating system isn't full of security holes (for one reason or another) and isn't a mobile device OS ported to real computers, especially if the OS wants you to use an app store. I like to play computer games, but I can live without computer games. I actually kind of like MS Office, but I'm just fine with LibreOffice.
The problem comes for the people who aren't all that great with computers. In general, most alternatives to Windows and OS X require at least a small amount of computer knowledge to really use.
Of the exceptions, the most common is Ubuntu. I'm really not a fan of Ubuntu (this has not always been the case), although I'll take it over Windows 8 any day. As far as I'm concerned, Ubuntu skims dangerously close to adware, and that seriously reduces its attractiveness. I'm also not terribly fond of its interface (that is, however, a matter of taste). There are other options out there such as ReactOS, which isn't past alpha, and thus not a good choice for "not computer people" and Linux Mint, based off of Ubuntu, which I have no opinion of, having never used it. Then there's Korora Linux. It's based off of Fedora, and unlike Fedora, comes with a lot of packages already installed to make things easy for "not computer people" and the lazy. I personally prefer the KDE desktop, but, for those who prefer a different desktop environment, its also available in GNOME, XFCE, Cinnamon, and Mate. If you're not certain what you want, you can (as with other Linux distros) create a "live cd" or "live USB drive" that lets you "test drive" the OS (and Desktop environment) before installing it.
I highly recommend Korora for the lazy and "not computer people" who are tired of Microsoft.